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NIISYLVANIA, ASSIGN'OBS T 11. I. no POINT DE HEIOUBS..& GOEPANY, OFWILMINGTON, DELAWARE, A CQBPORATION OF nmwann.

rnocnss or mimic anm-mnoanyrj It brewing. Application filed October 18,1920, Serial No. 417,838. Renewed mg; 24, 1926.

This invention relates tothe production of. alkyloxyl derivatives; ofnitro-aromatic compounds;-and it comprises, as a new process, thecondensation of an alkylo com- 5 pound such as an alcohol-or analkali-metal alcoholate, with a nitro-aryl compound, such.

' as a monoor poly-nitro-aryl halide, inthe presence of a substance,under pressure, such, for example, as an oxidizing agent, ca-

'10 pable of hinder' 'or preventing concurrent reduction andecomposition of the nitro compound.

In the preparation of certain compounds,

such as orthonitranisole, ara-nitrani'sole', l5 para-nitro-phenetole,etc, om. nitro-chlorobenzene, sodium hydroxide, and alcohol, .the mainreaction is accompanied, under ,certainconditions, by side reactionssuch as reduction, which resultin the formation of:

what'are probably azo or a zoxy compounds and decomposition products.These vnot only diminish the yield of the desired product, but also'makenecessary a purification or separation of the desired product from the'26 im urities.

e have discovered that a remarkable savin in time may be effected byconducting t e condensation under a comparatively a high temperature,and that undesirable side 30 reactions are almost entirely avoided, witha consequent increase in yield and purity of product, if there ispresent during the reactlon an oxidizing agent, prezferably incomparatively high concentration, as, for- .35 example, gaseous oxygenunder pressure,

which may advantageously be from 75 to chlorobenzene is added. Oxygen isthen introduced into 'a'free board space of -50% illustrated by thefolof the autoclave capacity, from a high pressure cylinder until apressure of 100-150 glbs. is reached. The temperature is then raised in3-5 hours to 100 C. and maintained'one hour. During the course of thereaction, the pressure is maintained at about 150 lbs. by passing inmoreoxygen. The charge is then cooled down to -40, the pressure is releasedand an additional .096 parts of fine dry 100% caustic soda are added.Oxygen: is then led in until the above pressure conditions arere-established, the charge'is again heated to 100 in 2-3 hours, and heldfor one hour, the temperature is again lowered and a second additionalcharge of .096 "parts of caustic soda is charged in oxygen is rechargedinto the autoclave and the mass is again heated to 100 C. in a similarmanner. This time the temperature is held at 100 C. until the maximumcondensation, as indicated by-ocontrol tests, has

'taken place. Maximum condensation takes place in 2-8 hours. When the'.reaction is complete, the product may be obtained after distilling offthe alcohol, or it may be isolated by crystallizing from the motherhquor solution. A yieldof 85-95% of the theoretical amount of paa-nitrophenetole is obtained. In the'above example there may ordinarilybe used any quantity of caustic soda between .35 and .50 parts for eachfour parts of ethyl alcohol, although we prefer to use a total of .492above.

2. Preparation of-ortfio-nih'oam'sole.

0.28 to 030 parts 100% caustic soda are dissolved in 3-5 parts of 95-99%methyl alcohol and after the addition of one 'part ofortho-nitro-chlor-benzene, air or oxygen or a mixture of the two isblown or pumped} parts in the manner described reaction is complete. Thedetermination is lutions such as that 0 made b control test. The excessalcohol is distille oil and the nitro-anisole is then drawn off, afterwashing with hot water to dissolve the sodium chloride andnitro-phenolates which are also formed in the reaction.

The yield of ortho-nitro-anisole will average 95-98% of theory. Theproduct may be satisfactorily used without purification for themanufacture of dianisidine, or anisidine.

Instead of caustic soda other alkalies may be used to romote thecondensation of the alcohol an nitro-ary'l halide.

Great advantages are possessed by our new process over known processes.By carrying out the reaction at a comparatively high temperature, and incomparatively high concentration, in the presence of an oxldizing agentunder pressure, it is ble to obtain a high yield of product, which ispractically free in most cases from side reaction products, in a shortperiod of time. Our process not only gives a comparatively pure productbut makes possible a high roduction through an increase in the capac-1ty of the lant. This increased capacity is due not on y to the shortertime required for a single run, but also the small quantity of alcoholneeded.

Although a gaseous oxidiz' agent such as air or oxygen is preferi ec l,iall when the reaction is carried out un or big pressure, our inventionalso includes the use of liquid or solid oxidizing agents, as forexample metal oxides such as manganese peroxide, sodium peroxide orcupric oxide; so-

f hydrogen peroxide; potassium ferricyanide, etc.

As examples of nitnoaryl ethers other than o-nitranisole and which maybe made by ej-new pr there may be mentioned dinitroanisole and-nitroanisole, using as starting materials initro-chlorobenzene andp-nitrochlorobenzene, tively, on the one hand and a methyl coholsolution of an alkali-metal hydroxide on the other.

The inner surface of the autoclave in which condensation is efiected mebe iron or may be enameled or glazed. ith a metallic surface there is anincreased tendency toward reduction, but is counteracted by theoxidlzmg' agent- We have described in detail the temperatures,preosurea, and other conditions of operation whichma be used to advantabut it will be an erstood that these conditions may be variedconsiderably without departing from our invention. Thus, although in thecases of nitroanisole and hitrop enetole a temperature between 95' and115 C. is preferred, a temperature either above or below this range maybe used.

. We claim 1. A prom of making alkyloxyl deriva- -nitrophenetole under ptives 0 nitro aromatic compounds which comprises heating a mixturecontaining an alcohol, an alkali-metal hydroxide, and anitrochlorobenzene in the presence of an oxidizing agent capable ofhindering the reduction of the mtro group.

4. A process of making 'a nitrophenyl ether which comprises heatin analcohol solution of an alkali-metal hy xide with a nitrochlorobenzene inthe prwence of gaseous oxygen ,under ressure.

5. A process oi m a nitrophenyl ether which comprises heating at atempera; ture between '95 and 115 C. a methyl alcohol solution of analkali-metal hydroxide with a nitrochlorobenzene in the presence ofgaseous oxygen under pleasure.

6. A process of a nitrophenyl etherwhich comprises heating ature between95 and 115 C. an alcoho solution of sodium hydroxide with' a nitmchlo inthe presence of gaseous oxygen under a total and 175 pounds.

7. A, proces of which com rises heating a mixture containfromaut3to5partsofmethyl alcoho a 7 about three tenths of a art of sodiumhydroxide, and one part 0 a nitrochlorobenzone, to a temperature of fromabout 105 to 110 C. in the presence of gaseous oxygen 8. A procem of u.a nitrophenyl ether which comprises eecting condensation between analcohol and a nitrochlorobenzene under pressure in the presence of anoxidizing agent and of a substance capable of promoting the condensationof the alcohol with said'nitrochlorobenzene.

' 9; A process of producing a nitrophenyl ether w ich comprisesefl'ecting condensation between an alcohol and a nitrochlorobenzene inthe presence of a substance capable of promoting said condensation andof an oxi aglent present in a state of comparatively liig concentration.

10. A garocess of making alkylo l derivatives 0 nitro aromatic compounwhich presume between 75 com rises heating a mixture containing aninakin ganitm-anisoh atatem Ora-0111950099 5,-

halide in'the presence of an oxidizing agent tween 95 and 115 C. in thepresence of an presentina state of comparatively high con.-' oxidizingagent present in a state of com- 10 centration. paratively highconcentration. g 11. A process of making alkylo l deriv- In testimonywhereof we afiix our signa 6 atives of nitro aromatic compoun s whichtures.

com rises heating a mixture containing an LYDE STUART PRATT. alco ol, analkali-metal hydroxide, and a EARL H. WELTZ. nitrochlorobenzene at atemperature be- WILLIAM LESTER liflLLS.

